Roving in bad van, go mad (8)
I believe the answer is:
vagabond
'roving' is the definition.
(I've seen this before)
'bad van go mad' is the wordplay.
'mad' indicates an anagram.
'bad'+'van'+'go'='badvango'
'badvango' is an anagram of 'VAGABOND'.
'in' is the link.
(Other definitions for vagabond that I've seen before include "Hobo" , "One wandering" , "An idle or dishonest wanderer" , "Down-and-out" , "Tramp" .)